This article presents an abstract structure capturing the essence of a mobile shared workspace (MSW), and how a particular MSW can be obtained by instantiating such structure. It is intended to assist designers of mobile groupware tools to conceive new products reusing other designers' knowledge. This approach facilitates the design of a particular MSW in an easy and fast way. We illustrate how the abstract structure can be instantiated in the development of MSWs to support hospital work and construction inspection activities.